Home conflict/issue

Finally got tired of using Laserweb because I’ve had constant issues with home moving, origins shifting and generally every job turns into a session of figuring out how to make the K40 submit to my will.
So first step was to get LightBurn, its consistant and I like it a lot. However, I still have issues which amount to origin and home causing some sort of offset. So the machine often starts at moderately different origins which moves the work and sometimes cause job which are not too big to end up out of bounds. I take it that if the machine goes out of bounds the slipping belt causes it to not return properly.

First, the hardware: K40 w/Cohesion Mini and Reprap Graphic display.
Home on the Reprap, works perfectly every time, top left where the limit switch is… Home on LightBurn is bottom left and I dont see how to change it.

I would like to have the origin near home and I also want to configure it to use all the area as it does not. So how do I do that? the file on the Cohesion?

You should probably learn about the different coordinate systems (G53…G59).

The machine controller defines where the machine origin is set when homing. Professional CNC machines usualy have the machine origin at top right, hobby machine more likely at bottom left. This has nothing to do with the host software!

Does your machine always set the same physical position (i.e. bottom left) as zero after homing?
If so, then you just need to move the origin of a work coordinate system (like G54) to the location where you want to have your work orign.

For example:
G90 G10 L2 P1 X20 Y200 sets position x20 y200 (absolute from the machine origin) as the origin for G54 coordinate system. Then G54 to select that coordinate system, and G0 X0 Y0 to move there.

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Thanks for the response Claudio, yes I should learn gCode basics like that. My issue was more that homing, origins and job placement were VERY inconsistent. Some times it was correct, mostly not. So thats why I though software.

As it turns out it was firmware. I used an update long ago from Cohesion I believe and did not realize my problems started with that as my use is not consistent, many jobs sometimes, then long down time before I use it again. Anyway, I found newer firmware listed as release 2.3 for Mini boards, batch 2 and 3.

While looking for clues as to which I might need I ran across a Lasergods post/article which gave a link to yet another firmware.bin. It was 100kb larger, I tried it and now 10 jobs later everything has worked perfectly. No change in config.txt either, so one way or the other the firmware was a problem with LightBurn. Now that I know there is some sort of relation between firmware and the program one uses, I will try different firmware if LaserWeb or whatever acts funny. OH, and not a surprise it also was the fix for out of bounds errors, so yes the coordinate system is crucial.

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I should add, that likely knowing the ins and outs of the coordinate system could have lead to fixing my issues without changing the firmware BUT thats another level of information and learning I did not have. Now that I understand how all this stuff works together, I will probably do the research and learning if I have issues in the future, like when I setup my 1600x1200 machine.

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